For someone who has an allergy, a substance that is harmless to most people causes their immune system to react and cause symptoms that can range from annoying to life threatening. The substance that causes the body's immune system to react this way is called an allergen. Indoor allergens such as dust mites, mold or pet dander are present year-round.

You could be allergic to house dust if you sneeze and wheeze most of the year, but noticeably more in the winter when you're spending more time indoors. Mold could be your problem if you develop allergy symptoms when you're in a damp basement or raking wet leaves. You're probably allergic to cats and dogs if allergy attacks occur when you're around these animals.

You may need to see an allergist if you can't pinpoint the cause of your problems. Once you know what's causing your symptoms, the following strategies can help you avoid the most common indoor allergies.

Dust allergies

Keep doors and windows closed to reduce indoor exposure to outdoor allergens, such as pollen.

Vacuum at least twice a week to control indoor allergens. Change bags often and consider purchasing a vacuum with a HEPA filter.

Remove wall-to-wall carpeting and cloth curtains, if possible. Clean them often if they can't be removed.

Consider treating carpets and upholstered furniture with tannic acid or benzyl benzoate to kill dust mites. Ask a professional furniture cleaner for rates.

Remove dust ruffles and heavy drapes from your bedroom. Also remove knickknacks and stacks of books and papers or keep them in covered storage units. Clean and dust the bedroom at least twice a week.

Keep dogs and cats out of the bedroom because pet dander is associated with greater numbers of dust mites. A lower room temperature and lower humidity help keep the dust mite population down.

Mold allergies

Clean and disinfect bathrooms weekly. To reduce mold, always run the exhaust fan during and after a shower. Keep under-sink areas dry.

Eliminate carpet and upholstered furniture in bathrooms or basements. They provide a perfect environment for mold and mildew to grow.

Fix leaky faucets immediately.

Wash towels often using hot water. Dry large beach towels in the dryer after use.

If you have a damp basement, bathroom, or any other room, use a dehumidifier.

Pet allergies

If possible, do not keep pets that have hair or fur. If you do have pets, keep them outside as much as possible and out of the bedrooms. Keep them off sofas, chairs, and other places where you sit, and away from coats and other clothing.

Wash your pets regularly. Wash your hands after playing with a dog, cat, or other pet.

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